How much does it cost to fix boiler error code No DHW function (CH OK)?

Typical repair cost for the boiler No DHW function (CH OK) fault is £140-£320 including labour.

No DHW function (CH OK) High

Boiler Fault Code No DHW function (CH OK)

Also written as NODHWFUNCTIONCHOK — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code No DHW function (CH OK) appears across 1 boiler brand and 1 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler is providing central heating but is failing to detect when you turn on a hot tap, meaning you have no hot water. (As reported on Worcester Bosch 24si II)

Pick your boiler brand for the No DHW function (CH OK) fix

Worcester Bosch No DHW function (CH OK) 1 model

Source

Information for the No DHW function (CH OK) fault code is sourced from the official service / installation manual for each model that displays it. Read more about how we source fault codes →

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026